Angry Republicans contend that dirty tricks at the polls tipped the balance of power in Pennsylvania

LYDIA COLON'S MOST PRESSING POLITIcal concern is garbage. A 5-ft. heap of it, piled outside an abandoned row house next door to her home in North Philadelphia, has broken through her chain-link fence. "I would vote 100 times, as long as they come and clean it up," says Colon, a 54-year-old native of Puerto Rico. That may be necessary, since she got no results from the two times she voted in last fall's election.

Colon says she hadn't intended to vote at all, but when a Democratic Party worker came to her door last October asking her to cast a ballot...